Intestinal brake inducing intraluminal therapeutic substance eluting devices and methods

ABSTRACT

Methods and devices create an intestinal braking effect, are non-invasive or minimally invasive, and may be reversible. These methods and devices are accomplished via stabilized implantable systems, and ingestible pills. In one embodiment, the implantable system comprises a device delivering a therapeutic substance to a target location within the gastrointestinal tract of a patient in order to initiate an intestinal braking effect which would promote sensations of satiety and stimulate excess weight loss for the patient.

PRIORITY

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 61/348,276, entitled “Intestinal Brake Inducing IntraluminalTherapeutic Substance Eluting Devices and Methods,” filed May 26, 2010,the disclosure of which is incorporated by reference herein.

FIELD OF INVENTION

The present invention relates to methods and devices that elute atherapeutic substance which aid in inducing an intestinal brakingeffect.

BACKGROUND OF THE INVENTION

When food content enters the intestines, an intestinal braking effectoccurs which helps to slow the passage of this food content therethroughin order to aid in the absorption of nutrients to in the body.Intestinal brake has been shown to initiate satiation more quickly andis theorized to play an important role in the effectiveness (both ExcessWeight Loss (EWL) and comorbidity resolution) of Roux-En-Y GastricBypass (RYGB) surgery. Procedures such as ileal transposition have beendeveloped based on the concept of delivery of substances with richnutrient/caloric content to the ileum and have been shown to beeffective in numerous animal models. However, known methods tend to beoverly invasive and often require a permanent perforation in theintestinal lumen. Accordingly, there is a need for creating anintestinal braking effect which is non-invasive or minimally invasive,and which may be reversible.

SUMMARY OF THE INVENTION

The present invention generally provides means for creating anintestinal braking effect which are non-invasive or minimally invasiveand which may be reversible. Numerous methods and devices are disclosedherein for accomplishing this effect. These methods and devices fallunder three general categories: implantable systems, methods ofstabilization of implants, and ingestible pills.

Numerous implantable systems for creating an intestinal braking effectare disclosed herein. These implantable systems may include means foreluting a therapeutic substance and are typically placed at or proximalto a desired delivery site. Examples of therapeutic substances includenutrients, hormones, hormone eluting cell stimulants, hormone elutingcell deterrents and the like. Preferably, the placement of these systemswould be accomplished by non-invasive or minimally invasive means. Thesesystems would typically comprise at least two sub-systems: an implantand a deployment device. Examples of such implants include intestinaldrug delivery stents, multi-reservoir stents, refillable intestinal drugdelivery stents, delivery systems for nutrient binding materials, chimeholding stents, and extraluminal choke rings, all of which will bediscussed in greater detail later herein. Examples of such deploymentdevices include inflatable delivery mechanisms, guide wire extenders,and self expanding stents, all of which will be discussed in greaterdetail later herein.

The methods of stabilization of implants generally comprise creating anartificially formed dead end branch or a loop with anastomosis in theintestines, both of which will be discussed in greater detail laterherein. These stabilization methods are generally minimally invasiveprocedures which allow the intestines to remain vascularized andconnected to mesentery. This allows any accompanying implant toestablish a continued impact on hormonal activity of the intestines,thereby increasing the effectiveness of this treatment.

Several ingestible pills creating an intestinal braking effect aredisclosed herein. In general, these specialized ingestible pills may beutilized to deliver therapeutic substances to targeted locations inorder to create the desired intestinal braking effect. These pills getaround the negative side effects associated with known systemic dosingof therapeutic substances for weight loss. Additionally, since thesepills may be administered orally, this method for creating an intestinalbrake has the added benefit of being non-invasive. Examples of suchingestible pills include a fat pill with nanochannels, a pressure wavepill, a stomach coating pill, and a pill to increase peristalsis, all ofwhich will be discussed in greater detail later herein.

As may be appreciated, any of the aforementioned devices and methodsdisclosed herein may be practiced either alone or in combination withany of the other disclosed devices and methods, where practical, withoutdeparting from the scope of the present invention, to achieve thedesired effect of creating an intestinal brake which is non-invasive orminimally invasive, and may be reversible in nature.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant.

FIG. 2 is schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant with a rechargeable drug-elutingreservoir.

FIG. 3 is a schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant with a rechargeable drug-elutingreservoir comprising a fill port attached therewith.

FIG. 4 is a schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant with a rechargeable drug-elutingreservoir comprising a fill port and a pressure sensing system attachedtherewith.

FIG. 5 is a schematic partially transparent view of delivery system fornutrient binding material.

FIG. 6 is a graph representing chyme levels in the body for a patientwith and without a chyme holding stent.

FIG. 7 is a schematic partially transparent view of a collapsibleimplant with a conical chyme pouch.

FIG. 8 is a schematic partially transparent view of a chyme holdingimplant and details thereof.

FIG. 9 is a schematic partially transparent view of a collapsibleimplant with absorbent material.

FIG. 10 is a schematic partially transparent view of an implantincluding an extraluminal choke ring.

FIG. 11 is a schematic partially transparent view of an implantincluding a wide band choke ring.

FIG. 12 is a schematic view of an inflatable delivery mechanism.

FIG. 13 is schematic partially transparent view of artificially formeddead end branches for stabilizing an implant.

FIG. 14 is a schematic partially transparent view of a procedure forforming an artificial dead end branch.

FIG. 15 is a schematic view of an artificially formed T-branch dead endfor stabilizing an implant.

FIG. 16 is a schematic partially transparent view illustrating the stepsfor creating a dead end branch using proven laparoscopic staplertechniques.

FIG. 17 is a schematic partially transparent view illustrating the stepsfor creating a dead end and holding an implant within the dead end usinga linear stapler, circular stapler and an extraluminal band.

FIG. 18 is a schematic partially transparent view of a loop anastomosisfor stabilizing an implant.

FIG. 19 is a schematic partially transparent view of a minimal segmentloop for stabilizing an implant.

FIG. 20 is a schematic partially transparent view of an excised portionof intestine reattached to the intestine via side-to-side anastomosisthereby creating a flow through chyme pouch having an implant therein.

FIG. 21 is a schematic partially transparent view of an ingestibleeluting device in its collapsed form.

FIG. 22 is a schematic partially transparent view of an ingestibleeluting device in its expanded form.

FIG. 23 is a schematic partially transparent view of a therapeuticsubstance pill with nanochannels and details thereof.

FIG. 24 is a schematic partially transparent view of a pressure wavepill and details thereof.

FIG. 25 is a graph representing pH changes in a patient's stomachthroughout the day.

FIG. 26 is a schematic partially transparent view of a pill to increaseperistalsis as it passes through the stomach and intestines of apatient.

DETAILED DESCRIPTION OF THE INVENTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those skilled in the art will understand that the devices andmethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the present invention is defined solely by the claims. Forexample, the features illustrated or described in connection with oneexemplary embodiment may be combined with the features of otherembodiments. Such modifications and variations are intended to beincluded within the scope of the present invention.

FIG. 1 is a schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant 100. In this particularembodiment, implant 100 is shown as a degradable intestinal stentpositioned in intestine 8, just past the ileocecal valve (see referenceindicia 10 in FIG. 4). Alternatively, implant 100 may be non-degradable.Implant 100 allows for the addition of nutrients and bio-activesubstances to the intestines, thereby inducing satiety through anintestinal braking effect. In certain embodiments, implant 100 may bedeployed during a standard colonoscopy procedure using a deploymentdevice attached to a flexible endoscope. This device and method wouldhave the benefits of inducing satiety through a non-invasive procedure,and is combinable with the single yearly recommended colonoscopy, thuspermitting monitoring of colon health and enabling weight loss in apatient. In one embodiment, implant 100 may be constructed from adegradable polymer having therapeutic substances therein. Non-limitingexamples of such therapeutic substances include nutrients and specificsatiety inducing bio-active substances such as pancreatic polypeptides(PPY), free fatty acids (FFA) and cholecystokinin (CCK). In alternativeembodiments, implant 100 may be coated with bioactive substances such asamino acids, glutamine, or lipids. These substances may elute over time.Implant 100 may be formed from a number of materials including coatedstring, mesh, fabric, buttons, tube, or any other suitable material.Implant 100 may further be rigid or flexible and may optionally beanchored to the wall of intestine 8 to secure its position. As may beappreciated, implant 100 may be of any desirable shape and size. Incertain embodiments, implant 100 may be helically shaped in order toallow flexibility along with intestine 8. Due to the stent shapeillustrated in FIG. 1, intestine 8 will begin to grow over implant 100in time, thereby encapsulating implant 100 in the intestinal wall, thusproviding the benefit of direct tissue for the therapeutic substanceswhich would aid in transfer of the therapeutic substances to thebloodstream. In another embodiment, implant 100 may be designed not toadhere to intestine 8. This may be accomplished, for example, by addinga lubricating means to the external surfaces of implant 100. In thismanner, implant 100 would be more easily removed from the body shouldthe patient so desire. In the case of implant 100 being a degradableintestinal stent, it may be desirable to construct implant 100 from apolymer or other substance having a full degradation period of a year orso in order to coordinate the full degradation of implant 100 with ayearly colonoscopy, during which a replacement implant 100 may beinstalled.

In regard to FIG. 1, numerous alternatives are envisioned. For example,in one embodiment, implant 100 may include means to create “pulsations”of therapeutic substances rather than simply providing a constantrelease of these therapeutic substances. Accordingly, implant 100 may beconstructed in a manner which provides alternating layers of therapeuticsubstance containing polymers and non-therapeutic substance containingpolymers. Similarly, the alternating layers may comprise layerscontaining different dosings or concentrations of the therapeuticsubstances or different therapeutic substances from the surroundinglayers. This may for example create a feeling of satiety, then areduction in that feeling, or may help maintain the effectiveness ofimplant 100 through time. Further, the therapeutic substance utilized inimplant 100 can be tailored to suit the intended location of the stent,taking into account factors such pH level exposure which may alter thelife span of implant 100. Additionally, implant 100 may be configured todeliver an electrical stimulation to the GI tract at a location such asthe ileum, and further may elute linoleic acid amongst its therapeuticsubstances. Non-limiting disclosure of the benefits of electricalstimulation of the ileum in the presence of linoleic acid in order toincrease glucagon-like peptide 1 (GLP-1) expression can be found in U.S.Patent Application No. US2010/0056948 A1, published Mar. 4, 2010,entitled STIMULATION OF SATIETY HORMONE RELEASE, which is incorporatedherein by reference in its entirety. In yet another embodiment, implant100 may comprise an intestinal stent containing an active substance suchas PPY or GLP-1 andoxytomodulin placed at the ileum. Further, the stentmay be in the form of a metal (e.g., cobalt chromium, stainless steel,Nitinol, etc.) or absorbable polymer ring or mesh affixed to thegastrointestinal (GI) tract by sutures. The active substance may be asynthetic which is analogous to a human hormone or animal derivedhormone.

The device and procedure outlined herein with respect to FIG. 1 isintended to induce satiety by introducing a therapeutic substance toactivate an intestinal braking effect via a therapeutic substanceeluting implant 100. The procedure has the further benefit of beingnon-invasive or minimally invasive, as well as being a reversibleprocedure should the patient or physician so desire. There are noanatomical changes to the GI tract, and placement of implant 100 may berealized endoluminally via a flexible endoscope or flexible endoscopicplatform. Implant 100 may be delivered through a working channel or overthe outside of the flexible endoscopic platform. Implant 100 may bedelivered in collapsed or expanded state and delivered to the desiredlocation within the GI tract either transorally or transanally. Further,the dosings and concentrations of the therapeutic substance(s) eluted byimplant 100 may be tailored to meet the individual needs of the patientand may further be enhanced to vary over time and may be localized tocontrol the delivery of hormone triggers to the desired receptors.

FIG. 2 is schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant 200 with a rechargeabledrug-eluting reservoir 202. In this particular embodiment, therapeuticsubstance eluting implant 200 is shown as a degradable intestinal stentpositioned in intestine 8, just past the ileocecal valve (see referenceindicia 10 in FIG. 4), which acts to trap rechargeable drug-elutingreservoir 202 thereon. As with the embodiments disclosed in FIG. 1, thisallows for the addition of therapeutic substances such as nutrients andbio-active substances to intestines 8 to induce satiety through anintestinal braking effect. Reservoir 202 may be recharged via anexternal source, such as through a port fixated to the patient's fasciaas is discussed later herein with respect to FIGS. 4 & 5.

FIG. 3 is a schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant 200 with a rechargeabledrug-eluting reservoir 202 comprising a fill port 300 attachedtherewith. In this embodiment, fill port 300 is connected to reservoir202 via tube 302. In certain embodiments, a valve 304 may be included atthe connection point between reservoir 202 and tube 302, or at any otherdesirable location, in order to maintain a desired fill level oftherapeutic substance within reservoir 202. When reservoir 202 fallsbelow the desired fill level, a surgeon may inject additionaltherapeutic substance into fill port 300 by means such as a Huberneedle. Alternatively, a transhepatic catheter may be inserted throughhepatic duct 14 (FIG. 4) and pass through liver 2 (FIG. 4), connectingto a subcutaneous fill port 300 for refilling reservoir 202.

FIG. 4 is a schematic partially transparent view of an intraintestinaltherapeutic substance eluting implant 200 with a rechargeabledrug-eluting reservoir 202 comprising a fill port 300 and a pressuresensing system 400 attached therewith. In this particular embodiment,the locations of the various components of the system are shown withinthe body of a patient. Following the natural path through the GI tract,food content enters through esophagus 1 and passes through cardia 4 intostomach 3. After some time, the food content is partially digested andbecomes chyme. This chyme exits stomach 3 through pylorus 5 intoduodenum 6. Duodenum 6, jejunum 7 and ileum 9 make up the three sectionsof small intestine 8. At the end of small intestine 8 in the ileum 9 isileocecal valve 10 which serves to connect small intestine 8 to largeintestine 11. Large intestine 11 is the final section of the GI tractand terminates at anus 12 through which solid waste may be expelled fromthe body. Aiding in the entire digestion process are liver 2 and gallbladder 13 which act to provide bile and other biochemicals necessaryfor digestion to duodenum 6 through hepatic duct 14. In FIG. 4, apressure sensing system 400 is positioned at cardia 4 to provide asignal to rechargeable drug-eluting reservoir 202 of intraintestinaltherapeutic substance eluting implant 200 when food is consumed. Thesignal sent initiates activation of a pump (not shown in FIG. 4) whichdelivers a therapeutic substance through reservoir 202 to induce anintestinal braking effect which would help to create or maintain asensation of satiety. As has been shown and described previously herein,fill port 300 has been provided to enable the system to be refilled withtherapeutic substance when necessary, and may be of the subcutaneoustype.

In regard to FIG. 4, numerous alternatives are envisioned. For example,in one embodiment, reservoir 202 may be attached to a micro-pump whichwould release therapeutic substance automatically at predeterminedpoints during the day in order to induce an intestinal braking effectwhich would help to create or maintain a sensation of satiety Thesesmaller doses are distributed along a more continuous schedule and serveto maintain the feeling of satiety longer through prolonged addition ofnutrients to the lower GI tract. As may be appreciated, additionalreservoirs and pumps may be added to the system described above todeliver the desired therapeutic substance. In another embodiment,reservoir 202 may be a degradable therapeutic substance infused foammaterial that may be injected behind implant 200 to fill the gap createdby the shape of implant 200. Over time, the foam material would releasethe therapeutic substance to induce an intestinal braking effect. Thisfoam material could be re-injected via a flexible member during anannual colonoscopy. In yet another embodiment, reservoir 202 may beconstructed from a semi-permeable membrane that would leach out atherapeutic substance over time. Similar to the previous embodimentdisclosed, this reservoir could be refilled by means of a flexiblemember inserted during an annual colonoscopy procedure. For example, theflexible member may comprise a Huber needle at one end which may beattached via tubing to a secondary reservoir, such as a saline bag,external to the patient during the colonoscopy. In still anotherembodiment, reservoir 202 may comprise a swallowable reservoir that iscaptured by implant 200. In one embodiment, implant 200 may be in theform of a stent having tines that protrude into intestine 8 and capturereservoir 202 as it is brought into position by the natural peristalsisof the digestive cycle. Reservoir 202 may be in the form of a hollowcylinder which allows chyme to pass therethrough, but contain atherapeutic substance in the reservoir body. The therapeutic substancemay then be released via slow perfusion, a small leak or aself-contained pump system. As the therapeutic substance is released,the diameter of reservoir 202 may decrease enough to allow it to passthrough implant 200. A replacement reservoir could then be swallowed andthe process would repeat.

FIG. 5 is a schematic partially transparent view of delivery system fornutrient binding material. As was described previously herein, foodcontent 500 enters the GI tract through esophagus 1 into stomach 3. Inthis particular embodiment, implant 502 resides within stomach 3.Implant 502 generally comprises a balloon implant that is tacked to thestomach as a long term implant. In one embodiment, implant 502 isdivided into two compartments separated by an intermediary wall 512,where one compartment contains a pH sensitive hydrogel 506 and the othercompartment contains a non-digestible fatty acid or high soluble fiberliquid 510. Hydrogels are cross-linked hydrophilic polymers that cancontain a large amount of water. By incorporating functional groups, ahydrogel can be made stimulus-sensitive, such that they undergo volumechanges in response to certain stimuli. Examples of such stimuli includepH changes, temperature changes, light, ion concentrations andelectrical fields. In one embodiment where the stimuli is pH change, asa pH level becomes acidic, hydrogel 506 becomes hydrophilic and attractswater through a pH sensitive membrane 504 and begins to expand. As a pHlevel becomes neutral or basic, hydrogel 506 becomes hydrophobic andcontracts, expelling any bound up water through porous membrane 508.When hydrogel 506 is in an expansion mode, not only does membrane 508allow the entire implant to grow and take up space in the stomach tocreate a satiety sensation, it also places pressure on the secondcompartment of implant 502 which contains non-digestible fatty acid orhigh soluble fiber liquid 510. As the second compartment of implant 502which contains non-digestible fatty acid or high soluble fiber liquid510 is placed under pressure by the expansion of hydrogel 506, membrane508 releases a small amount of the non-digestible fatty acid or highsoluble fiber liquid 510 contained therein, which then attaches to foodcontent 500 thereby slowing their absorption into the body as they passthrough the remainder of the GI tract. This in turn induces anintestinal brake as undigested nutrients and fatty acids enter ileum 9.Intermediary wall 512 may be constructed of a flexible elastomericmaterial such as silicone in order to allow a transfer of force from onecompartment to the other. In regard to FIG. 5, numerous alternatives areenvisioned. For example, in one embodiment, the first compartment may beconstructed of a fine mesh or a highly permeable expansible membranecontaining hydrogel. Examples of suitable hydrogels include chitosan,polyacrylamide (PAAM), and poly(2-Hydroxyethyl Methacrylate) (pHEMA)).

In another embodiment a chyme holding implant is provided. FIG. 6 is agraph representing chyme levels in the body for a patient with andwithout a chyme holding implant. The graph on the left of FIG. 6illustrates typical chyme levels in the body during the day without achyme holding stent. As may be appreciated, chyme levels are highestshortly after a meal and decrease over time, eventually crossing thehunger threshold which induces a sensation of hunger in the patient. Amore desirable graph is illustrated on the right of FIG. 6 where thechyme levels are maintained above the hunger threshold, therebymaintaining a sensation of satiety in the patient throughout the day.One means for creating such a graph is through the implantation of achyme holding implant within the intestine which would act to hold aportion of chyme therein to prevent its movement through the intestines,such that chyme is in chemical and/or biological contact with theintestinal cells responsible for intestinal brake, thereby inducing anintestinal braking effect. In one embodiment, chyme would be held longenough so that chyme from one meal would remain into the next.Alternatively, chyme may be held for longer periods of time if sodesired. In another embodiment, the implant protects the chyme thereinfrom further digestion through the use of chemical or mechanical means.By holding chyme from one meal to the next, the GI tract would betricked to behave as if food had just been ingested due to the chyme'stendency to induce the intestinal brake. This would allow the patient toeat less and achieve a desired weight loss.

FIG. 7 is a schematic partially transparent view of a collapsibleimplant 700 with a conical, flexible chyme pouch 702 positioned withinintestine 8. Implant 700 has an inlet 704 and an outlet 706. Peristalsisforces chyme in the direction indicated by arrow 708 due to narrow exit706 from pouch 702. Therefore, a select amount of chyme is delayed frommovement, which creates a semi-constant stream of chyme between meals,as was discussed previously herein with respect to FIG. 6.

FIG. 8 is a schematic partially transparent view of a chyme holdingimplant 800 and details thereof. In the embodiment illustrated in detail(A) of FIG. 8, chyme 802 may be funneled into an expansible slow leakreservoir 804 to achieve the desired effect of time released chyme. Inone embodiment, implant 800 may be suspended by wire elements 806 inintestine 8 which are centered on stent 814 in a configuration thatallows some chyme to bypass the reservoir via bypass channels 808 andsome to be trapped within reservoir 804. As chyme is accumulated,reservoir 804 would expand. The limited size of slow leak catheter 810of reservoir 804 would allow the accumulated chyme impelled by thepressure of reservoir 804 returning to its unexpanded state to slowlydrip therefrom long after a meal was over. In this manner, chyme mayfurther be prevented from retrograde motion by a one-way valve means atoutlet 812, such as a duck bill valve, located between implant 800 andreservoir 804. This increases the capacity of the implant to hold andrelease chyme, thereby extending the sensation of satiety in thepatient. The entire assembly may be located within a stent 814positioned at a target location within intestine 8. A cross-sectionalview of the arrangement and interactions of implant 800, reservoir 804,slow leak catheter 810 and one-way valve 812 are shown in detail (B) ofFIG. 8.

FIG. 9 is a schematic partially transparent view of a collapsibleimplant 900 with absorbent material 902. In this particular embodiment,collapsible implant 900 is shown with a piece of absorbent material 902affixed thereto, and is affixed within intestine 8 at a target location.In one embodiment, material 902 comprises a hollow cylindrical sponge.As peristalsis moves chyme through the GI tract, some chyme containedwithin material 902 is pushed out, and flows in a direction indicated byarrow 904. Subsequent peristaltic motions repeat this effect. Therefore,some amount of chyme is delayed from movement through the GI tract,thereby creating a prolonged sensation of satiation in a patient.

FIG. 10 is a schematic partially transparent view of an implant 1000including extraluminal choke ring 1002. In the embodiment illustrated indetail (A) of FIG. 10, implant 1000 is implanted at a target locationwithin intestine 8 and a choke ring 1002 is positioned extraluminallyproximate a groove 1004. In detail (B) of FIG. 10, choke ring 1002 iscrimped such that it fits within groove 1004 in a manner that securesimplant 1000 in place within intestine 8, yet prevents necrosis.Although illustrated as a round wire, it is contemplated that choke ring1002 may be formed in different configurations to include features suchas flat or undulating cross-sections, locking features, and the like,without departing from the scope of the present invention. Further, itis contemplated that this system may be implanted using non-invasive orminimally invasive methods such as single site laparoscopy.

FIG. 11 is a schematic partially transparent view of an implant 1100including a wide band choke ring 1102. In this particular embodiment,implant 1100 is positioned within intestine 8 in a similar manner tothat of the embodiment described above in FIG. 8. However, in thisparticular embodiment the external surface 1104 of implant 1100 does notinclude a groove and is formed of a mesh material. The mesh materialcomprising external surface 1104 causes numerous contact points betweenwide band choke ring 1102 and implant 1100 through intestine 8, therebysecuring implant 1100 within intestine 8.

FIG. 12 is a schematic view of an inflatable delivery mechanism 1200.Mechanism 1200 is an exemplary means for delivering an implantabledevice such as stent 1202 into the GI tract as is detailed in previousembodiments of the present invention. In one embodiment, mechanism 1200attaches to a flexible endoscope 1204 and mechanism 1200 is inflated tosecure stent 1202 externally thereon. When stent 1202 is delivered tothe desired location, mechanism 1200 is deflated thereby releasing stent1202. At that point, mechanism 1200 and endoscope 1204 can be removedfrom the patient's body and mechanism 1200 can be removed from endoscope1204. In an alternative embodiment, mechanism 1200 may stay in placewith stent 1202 to serve as a reservoir of therapeutic substance. Thiswould obviate the need to perform a separate fill procedure in situ upondeployment. It should be noted that implantation of a device within theGI tract may necessitate a guide wire extending means in order to reachthe target area within the GI tract, since such locations typically fallbeyond the ileocecal valve and thus may be out of reach for knowncolonoscopes.

FIG. 13 is schematic partially transparent view of artificially formeddead end branches for stabilizing an implant 1300. As is shown indetails (A) and (B) of FIG. 13, intestine 8 is transected at a location1302, and an end-to-side anastomosis is performed in order to reconnectproximal portion 1306 and distal portion 1308 of intestine 8, thusleaving a branch portion 1310 in place with an implant 1300 therein.Branch 1310 and implant 1300 together serve as a retrograde dead endwithin intestine 8. Alternatively, a side-to-side anastomosis may beperformed in place of the end-to-side anastomosis disclosed, so long ascare is taken to prevent formation of a second blind pouch which maycollect chyme. In either procedure, intestine 8 remains vascularized andconnected to mesentery. Thus, implant 1300 may continue to have animpact on hormonal activities of intestine 8. Certain embodiments ofimplant 1300 may include an occluded end portion 1312 in order toprevent any chyme passage. As may be appreciated, implant 1300 may be ofthe drug eluting type disclosed previously herein. As yet anotheralternative, intestine 8 may undergo an end-to-end anastomosis in orderto form a continuous section. Details of the end-to-end anastomosis aregiven in FIG. 15.

FIG. 14 is a schematic partially transparent view of a procedure forforming an artificial dead end branch. Details (A), (B) and (C) of FIG.14 outline the procedural steps for forming an artificial dead endbranch as described in FIG. 13. Detail (A) of FIG. 14 illustratesintestine 8 prior to end-to-side anastomosis. Detail (B) of FIG. 14illustrates intestine 8 transected into proximal portion 1306 and distalportion 1308 by means of a linear cutting device (not shown). Detail (C)of FIG. 14 illustrates the formation of a dead end branch viaimplantation of implant 1300 and end-to-side anastomosis at junction1400.

FIG. 15 is a schematic view of an artificially formed T-branch dead endfor stabilizing an implant. Details (A), (B) and (C) of FIG. 15 outlinethe procedural steps for forming an artificially formed T-branch deadend for stabilizing an implant via an end-to-end anastomosis as wasbriefly mentioned in the description of alternative embodiments of FIG.13. Detail (A) of FIG. 15 illustrates intestine 8 having cut lines 1502and 1504 shown therein. Together, cut lines 1502 and 1504 serve tocreate portion 1506 of intestine 8, which is shown to be excised indetail (B) of FIG. 15. Detail (C) of FIG. 15 illustrates the formationof an artificially formed T-branch dead end for stabilizing an implant(not shown) where excised portion 1506 is reattached to intestine 8 atjunction 1510 and stapled at its opposing end to create a dead endbranch 1508. Further, cut lines 1502 and 1504 are connected to form anend-to-end anastomosis 1512.

FIG. 16 is a schematic partially transparent view illustrating the stepsfor creating a dead end branch using laparoscopic stapler techniques. Afirst step (A), illustrates intestine 8 in an unaffected state. In asecond step (B), intestine 8 is folded to create an overlap 1600. In athird step (C), access is gained via aperture 1602 which is formed bycutting tool 1604. In a forth step (D), stapler 1606 is inserted intofolded intestine 8 through aperture 1602. In a fifth step (E), stapler1606 secures overlap 1600 together with staples 1608. In a sixth step(F), stapler 1606 is removed through aperture 1602 and staples 1608 holdoverlap 1600 together. In a seventh step (G), a therapeutic substancereservoir 1610 with a slow drip catheter portion 1612 is inserted intointestine 8 through aperture 1602. In an eighth and final step (H),aperture 1602 is closed and an external ring clamp 1614 is appliedbetween the tissue surrounding reservoir 1610 and the remainder ofintestine 8 such that reservoir 1610 is maintained within the dead endbranch portion formed and catheter 1612 is positioned in the flow pathof intestine 8 in order to provide a slow drip therapeutic substancewhich will initiate an intestinal braking effect and thereby create ormaintain a sensation of satiety in the patient.

FIG. 17 is a schematic partially transparent view illustrating the stepsfor creating a dead end and holding an implant 1610 within the dead endusing a linear stapler, circular stapler and an extraluminal band. Steps(A) and (B) illustrate intestine 8 being transected into proximalportion 1306 and distal portion 1308 by means of a linear cutting device1700. In a third step (C), proximal portion 1306 of intestine 8 isstapled at its transected end to create a dead end, and a side-to-sideanastomosis 1706 is performed to reconnect proximal portion 1306 anddistal portion 1308. In a forth and final step (D), a therapeuticsubstance reservoir 1610 with a slow drip catheter portion 1612 isinserted into intestine 8 through open transected end 1704 of distalportion 1308 of intestine 8, which is then stapled closed and anexternal ring clamp 1708 is applied between the tissue surroundingreservoir 1610 and the remainder of intestine 8 such that reservoir 1610is maintained within the dead end branch portion formed and catheter1612 is positioned in the flow path of intestine 8 in order to provide aslow drip therapeutic substance which will initiate an intestinalbraking effect and thereby create or maintain a sensation of satiety inthe patient.

FIG. 18 is a schematic partially transparent view of a loop anastomosisfor stabilizing an implant 1804. Detail (A) of FIG. 18 illustratesintestine 8 prior to loop anastomosis. Detail (B) of FIG. 18 illustrateswherein a loop 1800 is formed by bringing two distal points of intestine8 together with a side-to-side anastomosis 1802 having flow channelstherethrough though which chyme 1806 passes. In this manner, loop 1800houses implant 1804 thereby keeping it from the chyme path, yet allowingit to initiate an intestinal braking effect in intestine 8 as withpreviously disclosed embodiments of the present invention. In someembodiments, occluded implants may be further provided to prevent chyme1806 from entering loop 1800 which may cause blockage or infection.

FIG. 19 is a schematic partially transparent view of a minimal segmentloop for stabilizing an implant 1900. Detail (A) of FIG. 19 illustratesintestine 8 having implant 1900 positioned therein and cut lines 1502and 1504 thereon, prior to loop anastomosis. Together, cut lines 1502and 1504 serve to define proximal portion 1306 and distal portion 1308and further to create portion 1506 of intestine 8, which is shown to beexcised and reattached via loop anastomosis in detail (B) of FIG. 19.Detail (B) of FIG. 19 illustrates the completed loop anastomosisprocedure wherein excised intestine portion 1506 serves as a loop whichis attached to intestine 8 at end 1908 and end 1910 via end-to-sideanastomosis. Further, cut lines 1502 and 1504 are brought together atjunction 1906 via end-to-end anastomosis. In this manner, the loopformed by portion 1506 houses implant 1900 thereby keeping it from thechyme path, yet allowing it to initiate an intestinal braking effect inintestine 8 as with previously disclosed embodiments of the presentinvention. In some embodiments, occluded implants may be furtherprovided to prevent chyme 1912 from entering the loop formed by portion1506 which may cause blockage or infection.

FIG. 20 is a schematic partially transparent view of an excised portion1506 of intestine 8 reattached to the intestine via side-to-sideanastomosis thereby creating a flow through chyme pouch 2000 having animplant 2002 therein. As was disclosed previously herein with respect toother embodiments, implant 2002 may be of the flow through and/or slowdrip type and may further have therapeutic substance eluting propertiesin order to initiate a desired intestinal braking effect. As analternative, implant may be of the sponge type as was discussedpreviously herein in regard to FIG. 9, wherein peristalsis moves chymethrough the GI tract, such that some chyme contained within the spongematerial of implant 2002 is pushed out, and flows in a directionindicated by arrow 2004. Subsequent peristaltic motions repeat thiseffect. Therefore, some amount of chyme is delayed from movement throughthe GI tract, thereby creating a prolonged sensation of satiation in apatient.

FIG. 21 is a schematic partially transparent view of an ingestibleeluting device 2100 in its collapsed form. In one embodiment, device2100 has a short term degradable exterior coating 2102 which containsthree collapsed pill sections 2104, 2106 and 2108, as well as an axle2110 therein. In one embodiment, axle 2110 is formed of a bioabsorbablepolymer. Further, pill sections 2104, 2106 and 2108 may be formed of oneor more types of therapeutic substance. In another embodiment, device2100 may contain apertures which allow passage of chyme and the liketherethrough. As may be appreciated, device 2100 may take on any numberof sizes and shapes, but in certain embodiments device 2100 is sized andshaped such that it cannot pass through the ileocecal valve withoutundergoing degradation of its degradable components.

FIG. 22 is a schematic partially transparent view of the ingestibleeluting device 2100 in its expanded form. In this particular embodiment,pill sections 2104 and 2106, and axle 2110 are shown expanded radiallyfrom a center point at angles of roughly 120° from one another, althoughother angles are anticipated depending upon factors such as the numberof pill layers in device 2100. As may be seen in FIG. 22, none of thecomponents of device 2100 are permitted to block passage of chyme andother substances through ileocecal valve 10 due to their radiallyexpanded configuration. As was discussed previously herein, device 2100is sized and shaped such that it cannot pass from ileum 9 to largeintestine 11 through ileocecal valve 10 without undergoing degradationof its degradable components. However, once the degradable components ofdevice 2100 have become depleted, the remaining components may then passthrough ileocecal valve 10 and through the remainder of the GI tractnaturally.

FIG. 23 is a schematic partially transparent view of a therapeuticsubstance pill 2300 with nanochannels 2308 and details thereof. Detail(A) of FIG. 23 illustrates a cross-sectional view of pill 2300 havingsidewall 2302 and end caps 2306 containing a therapeutic substance 2304therein. In this particular embodiment, therapeutic substance 2304comprises fat or glucose, although numerous other therapeutic substancesmay be utilized in addition to or in place of fat or glucose. In certainembodiments, therapeutic substance 2304 acts to stimulate GLP-1 over ashort period of time as it passes by K-cells within the duodenum andthen again stimulating GLP-1 through the L-cells within the ileum inorder to induce an intestinal braking effect. The principle beingtriggering the signaling pathway for GLP-1 stimulation without thenegative effects associated with ingesting additional fat or glucose. Ascan be seen in details (B) and (C), sidewall 2302 has a thickness Tthrough which nanochannels 2308 pass. Nanochannels 2308 may be patternedand sized as desired to enable the desired amount of fluid communicationtherethrough, and may further serve as an enzyme barrier to preventdigestion of therapeutic substance 2304 contained within pill 2300, butstill allow for the passage of GLP-1 which would allow the body'ssignaling pathway to identify the presence of therapeutic substance 2304in the GI tract in order to stimulate GLP-1. In certain embodiments,sidewall 2302 may be constructed of polymeric material or of silicon. Incertain other embodiments, an adhesive may coat a portion of pill 2300thereby allowing it to be easily secured in a desired location withinthe GI tract.

FIG. 24 is a schematic partially transparent view of a pressure wavepill 2400 and details thereof. Detail (A) of FIG. 24 illustrates across-sectional view of pill 2400 having sidewall 2402 and end caps 2406containing therein an electromechanical system 2404 for creating pulsewaves 2408. In this particular embodiment, sidewall 2402 is formed of asemi-flexible material that allows outward expansion, as is shown indetail (B) of FIG. 24, which aids in the production of pulse waves 2408.The creation of pulse waves 2408 may be done for example by generating alow frequency pressure wave using electromechanical system 2404 which,if done in the ileum, would stimulate the interaction of chyme with thevilli and microvilli, and thus with the L-cells of the ileum. Suchstimulation would in turn initiate an intestinal braking effect creatinga sensation of satiation in the patient. In certain embodiments,electromechanical system 2404 may consist of a MEMS transducer thatwould be capable of creating an abrupt expansion of sidewall 2402 whichwould in turn propagate pulse waves 2408 through the chyme within theimmediate proximity of pill 2400. As may be appreciated, pill 2400 maycontain its own power source and be activated in the stool, or may be apassive type device. Further, additional coatings and barrier layersthat may affect the travel rate and/or chemical/hormonal characteristicsof pill 2400 are also contemplated. As with previous embodiments of thepresent invention, pill 2400 may also deliver a therapeutic substance ifso desired.

FIG. 25 is a graph representing pH changes in a patient's stomachthroughout the day, as taken from Simonian, H. P., Vo, L., Doma, S.,Fisher, R. S., Parkman, H. P., “Regional Postprandial Differences in pHwithin the Stomach and Gastroesophageal Junction”, Digestive Diseasesand Sciences, pgs. 2276-2285; 50(12) 2005. As may be seen from thisgraph, physiological changes of the digestive system between fasting andconsumption may be described in terms of changes in gastric acidity asmeasured using pH (the log concentration of hydronium ion concentration,or log [H+]). The pH scale spans from 1 (acidic) to 14 (basic), with 7.0being neutral. During the fasting state, the stomach pH is low (acidic).With meal ingestion, there is buffering of intragastric acidity with anelevation of gastric pH. The change in pH occurs rapidly with theinitiation of consumption as food enters into the stomach. This changealso occurs even in light of the secretion of gastric acids continuouslyduring consumption. The buffering capacity of foods, including acidic or“spicy” foods is sufficient to provide a significant change in gastricpH.

In regards to the information disclosed in the graph of FIG. 25, it isdesirable to treat a patient with a pill which creates a coating withinthe stomach that helps to induce an intestinal braking effect. In oneembodiment, such a pill would accelerate the delivery of fatty acidcompounds and/or other therapeutic substances to the body to enable areduction in food consumption or the sensation of hunger in a patient.In one embodiment, when such a pill is ingested, chemical compoundswhich terminate in long chain fatty acids are contained within the pilland act to bind to the interior walls of the stomach at acidic pHlevels. Upon initial consumption of a meal, compounds release which actto neutralize the pH levels in the stomach. The bound chemical compoundsare then released from the stomach walls into the stomach in highconcentrations at the start of the meal, thus allowing for a more rapidstimulation of the ileum to initiate an intestinal braking effect. Itmay be desirable to include longer chained fatty acids such as palmitic,lignoceric acid, and hexacosanic acid in order to decrease thedigestibility of the substance, thereby increasing the likelihood thatthe substance reaches the ileum.

FIG. 26 is a schematic partially transparent view of a pill 2600 toincrease peristalsis as it passes through stomach 3 and intestines 8 ofa patient. Detail (A) of FIG. 26 illustrates the second pill 2600 of atwo pill system. In one embodiment, a first pill 2604 comprising anutrient pill having a degradable outer layer is ingested orally by apatient. A short time later, second pill 2600 is ingested orally. Incertain embodiments, pill 2600 is an electronic pill having low voltageelectrodes 2602 thereon. In such embodiments, electrodes 2602 are pulsedto create an increase in the peristaltic rate of the GI tract. Details(B), (C), (D) and (E) show the progression of nutrient pill 2604 andelectronic pill 2600 through the GI tract utilizing the increasedperistalsis created by electronic pill 2600 as a means to speed deliveryof the pills to the target location. As may be appreciated, alternativeembodiments may comprise a combined electronic and nutrient pill, or mayutilize other known means for increasing peristalsis.

One skilled in the art will appreciate further features and advantagesof the invention based on the above-described embodiments. Accordingly,the invention is not to be limited by what has been particularly shownand described, except as indicated by the appended claims. Allpublications and references cited herein are expressly incorporatedherein by reference in their entirety.

I/We claim:
 1. A device for implantation within a gastrointestinal tractof a patient, said device comprising an expandable tubular member, saidtubular member comprising a pH sensitive substance which changes a sizeof said tubular member in reaction to changes in pH levels within saidgastrointestinal tract of said patient.
 2. The device of claim 1,wherein said tubular member is capable of eluting a therapeuticsubstance to cause an intestinal brake effect, wherein said therapeuticsubstance is eluted by a mechanism selected from pulsation, constantrelease, and a combination thereof.
 3. The device of claim 1, whereinsaid wherein said tubular member is capable of eluting a therapeuticsubstance selected from at least one of fat, glucose, nutrients,hormones, hormone eluting cell stimulants, hormone eluting celldeterrents, pancreatic polypeptide, free fatty acid, cholecystokinin,amino acids, glutamine, lipids, glucagon-like peptide-1, or combinationsthereof.
 4. The device of claim 1, wherein said device comprises aswallowable pill device, wherein said pill is selected from a pill withnanochannels, a pressure wave pill, a stomach coating pill, a pill toincrease peristalsis, and combinations thereof.
 5. The device of claim1, wherein said device comprises a swallowable pill comprisingnanochannels that allow fluid communication and passage of glucagon-likepeptide-1 therethrough and which serve as an enzyme barrier to preventdigestion of therapeutic substances contained within said swallowablepill.
 6. The device of claim 5, wherein said pill comprises layers,wherein said layers are selected from therapeutic-containing layers,non-therapeutic containing layers, and combinations thereof.
 7. Thedevice of claim 1, wherein said device comprises a rechargeable drugeluting reservoir, said reservoir in a form selected from a degradabletherapeutic substance infused foam, a semi-permeable membrane capable ofreleasing a therapeutic substance over time, a hollow cylinder whichallows chyme to pass through, and combinations thereof.
 8. The device ofclaim 1, wherein said device comprises a chyme holding device.
 9. Thedevice of claim 1, wherein said device comprises a fill port and apressure sensing system.
 10. The device of claim 1, wherein said deviceis capable of producing pulse waves to stimulate the interaction ofchyme with the L cells of the ileum to create an intestinal brakeeffect.
 11. The device of claim 1, wherein said tubular member isconfigured to deliver an electrical stimulation to the ileum in thepresence of linoleic acid.
 12. The device of claim 1, wherein saidtubular member is degradable.
 13. The device of claim 1, wherein saidtubular member is positioned in the intestine just past the ileocecalvalve.
 14. The device of claim 1, wherein said tubular member is affixedto the wall of the intestine.
 15. The device of claim 1, wherein saidtubular member comprises a lubricant.
 16. A method of inducing satietycomprising a. implanting a stent within a lumen of a gastrointestinaltract; b. retaining a portion of chyme that flows by the stent within abody of said stent; and c. re-releasing the retained chyme from saidstent into the gastrointestinal tract at a predetermined rate slowerthan a rate caused by natural peristalsis.
 17. The method of claim 16wherein said step of retaining a portion of chyme that flows by thestent within a body of said stent comprises absorbing said chyme withinsaid stent.
 18. The method of claim 16 wherein said step of retaining aportion of chyme that flows by the stent within a body of said stentcomprises physically obstructing said chyme within said stent.
 19. Themethod of claim 16 comprising at least one additional step of the stepof: a. stabilizing said stent without disturbing vascularization of theintestines by performing a procedure selected from creating anartificially formed dead end branch; b. forming a loop with anastamosisin the intestines; or c. a combination thereof.
 20. A method ofproducing satiety comprising: a. surgically accessing a gastrointestinaltract of a patient; b. splitting said tract into a first lumen forpassage of nutrients and a second lumen; c. implanting a device withinsaid second lumen; and d. eluting a satiety inducing substance from thedevice into the gastrointestinal tract.